Abstract

It appears that light may be thrown on the nature of moral principles if they are construed as moral laws analogous to ceteris-paribus laws of nature. Luke Robinson objects that the analogy either cannot explain how moral principles are necessary or cannot explain how obligations can be pro-tanto; and that a dispositional account of moral obligation has explanatory superiority over one in terms of moral laws. I explain the analogy, construing laws of nature as necessary relationships after the fashion of William Kneale and Karl Popper. I then show that Robinson’s objections are mistaken and that if the difference between a dispositional account and a law account is not merely verbal, then it is the law account that is superior. I also dispel the common confusion between the necessity of laws and the existence of forces.